The present invention relates to a pressure sensor that detects a pressure.
Japanese Laid-Open Patent Publication No. 6-34455 describes a pressure sensor that includes a diaphragm, a force transducer, and a force transmission block. The force transducer outputs an output signal that changes according to a pressure. The force transmission block is coupled to the force transducer. The pressure sensor detects the pressure applied to the diaphragm by transmitting the pressure to the force transducer through the force transmission block.
The output signal of the force transducer of the pressure sensor changes according to the temperature as well as the pressure. That is, even when the pressure transmitted to the force transducer is constant, changes in the temperature change the output signal. Thus, the pressure sensor of the above publication performs a temperature compensation operation on the output signal of the force transducer to eliminate the influence of the temperature. The pressure is detected based on the output after the operation.
The pressure sensor described above pre-stores a compensation factor for the temperature compensation operation. Force transducers vary in output characteristics. In order to accurately correct the change in the output signal of each element caused by a change in temperature, the pressure sensor needs to store a compensation factor that is determined in accordance with the output characteristic of the element. This may increase the manufacturing steps of the pressure sensor and the manufacturing costs.